Answer:
In order to propose a hypothesis, there is a need to first see the function of gills in fishes. The gills of fishes comprise blood vessels that exhibit inherited tendencies of getting oxygen out of the water, which was consumed by fishes from their mouths. These gills also comprise thin walls, and when water moves over these walls of blood vessels, the oxygen from water moves into the blood, and then this oxygen-enriched blood goes to various organs.
Thus, one of the hypotheses in the given case, can be the number of blood vessels, which are found in the gills of the mentioned freshwater fish to be higher in comparison to the blood vessels found in the normal fishes, and apart from this, the surface area of the thin walls, which are found in the gills is also more in the new species of freshwater fish.
Answer: Antibiotics targets the synthesis of protein, nucleic acid, folate and cell wall.
1. Synthesis of protein; antibiotics binds to either 30s or 50s ribosomal subunits blocking the polypeptide from the exiting the tunnel thus inhibiting a full completion of protein expression or production.
2. Nucleic acid synthesis; Antibiotics also act by inhibiting genetic expression, DNA transcription and replication where DNA makes exact copies of itself, as well as RNA molecules preventing bacterial growth.
3. Cell wall synthesis; Inhibition of cell wall synthesis in microorganisms will prevent it from replication and growth.
4. Folate synthesis; Folic acid also known as vitamin B9 helps in DNA replication and cell division. Folate antagonists such as aminopterin kills bacteria by preventing folic acid production required for DNA replication.
Aluminum is a shiny, silvery white colored metal that is light in weight and strong.